Rock-drill.



Nm '784,173r

PATENTED MAR. 7, 1905. G'. T. MGORMIGE.

ROCK DRILL..

APYLIOAToN FILED APR.11, 1904.

2 SHEETS-SHEET l.

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NG. 784,173. PATENTED MAR-7, 1905. u. T. MUGORMIGK.

ROCK DRILL.

AYPLIOATION FILED APB. 11. 1904,

2 SHEETS-SHEET 2.

W/:Tv/ Gyms TL McCormick.

NTED STATES Patented March 1905.

PATENT eeen-Deum..

SPECIFICATION forming part of Letters Patent No. 794,173, dated March 7, 1905.

Application iiled April 11,1904. Serial No. 202,578.

Be it known that I, Crans rl. MeCoimieK, a citizen of the United States, residing at the city ot' Fredericktown, county of Madison, in the State of Missouri, have invented acertain new and useful Rock-Drill, oit' which the following is such a full, clear, and exact description as will enable any one skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, forming part of this speciiication.

My invention relates to rock-drills,and more particularly to that class oi drills in which recilirocating motion is imparted to the tool by a piston or pistons driven by compressed air, steam, or other suitable motive iluid.

My invention consists in part in the combination with a cylinder provided with a piston and having an open end at one side oi' said piston, of means for exhausting motive fluid from the other side of said piston and discharging it into the side ot said cylinder having the open end.

My invention also consists in part in the combination with a cylinder, of a piston in said cylinder, a valve composed oi' two parts, an exhaust-port in one of said parts, a snppl y-port extending through both of said parts, a by-pass for actuating one of said parts, a plurality of openings to said by-pass, and a second by-pass for operating' the other of said on the lines 3 3 and i Il, respectively. oi Fig. 5. Fig. 5 is an enlarged section on the line 5 5 of Fig. 1, and Fig. 6 is an enlarged end view.

Like marks oi reference reier to similar parts in the several views oi the drawings.

10 is the cylinder or casingoig the drill. This cylinder is divided bya partition 'l1 into two l substantially equal parts. lassing through the partition l1 is a piston-rod 12, bearingan upper piston l?) and lower piston l-l. The lower end ot' the piston-rod ,l2 is arranged to receive and secure a drill 15. The cylinder 10 is open both at the top and bottom end, the bottom end being completely open, while the top end is partly closed by means oi a cap 16 for the ratchet mechanism, hereinafter to be described. An opening' 1T `lor the passage of air is lelt, however, so that the cylinder is substantially open at both ends. prevent particles oi dust and other `foreign matter from being drawn into the open ends of the cylinder by the movement ol? the pistons therein, l provide discharge -ports 9, which discharge the exhaust motive lluid into the open ends oi the cylinders. The inner ends oi' the discharge-ports 9 communicate with a Valve-casing 18, extending across the cylinder 10. Hthin this valve-casing 18 a cylindrical-valve composed of an outer part 19 andinner part 20. ln the outer part A19 are formed two exhaust-ports 21, which are adapted to place the inner ends oi' the exhaustport 9 in communication with the ports 22, leading to the cylinder. Passing through both parts 1 9 and 2O is a supply-port 23.

1n order to indei'iendently operate the parts 19 and 2O oi the valve, l provide the part 19 at one end with a wing 24, movingin a chamber 25, and leading Vfrom this chamber 25 to points near the ends ol" the cylinder are by-passes 2.6. I provide the part Q0, at the opposite end oi the valve, with a wing 27, working in a chamber 28, which chamber coml'nunicates with bypasses 99. ln each oi the lay-passes 29 isa hollow cylindrical member 30, provided with a handle 3l or other means lor rotatingit. By moving this hollow cylindrical member 30 the by-pass 2.9isplaced in communication with the cylinder through one or the other ot ports 32. The motive il uid is supplied to the valve mechanism through an inlet 33, liig. l.

Carried in the cap 16, hereinbeiiore re'lerred to, is a ratchetwheel 35, coi'iperating with pawls 36, which allow the said wheel to move ment in the opposite direction. lilxtending downwardly lrom the ratchet-wheel isa ln order to' partly in one direction, but 'prevent its moveable recesses in the cylinder 10.

spirally-ribbed stem 37, which enters the hollow upper end of the piston-rod, and thus causes the said rod to turn a slight distance upon each upward stroke, so as to prevent the edg'e of the drill from striking in the same plane in the various strokes.

40 is the supporting member, which is preferably semicylindrical in form and is provided with a projecting portion 41 for securing' the drill in position. Secured to the supporting member by means of bolts 42 are a pair of guides 43. These guides 43 engage with suit- Carried by the lower end of the supportingmember 40 and the guides 43 is a bearing 44, in which is journaled one end of a screw-threaded rod 45. Y

rlhe opposite end of this rod 45 is provided with a handle 46, and adjacent to the handle is a bearing 47, attached to the upper ends of the guides 43. This bearing 47 is also connected to the upper end'of the supporting' member 40'by means of a brace 48. The rod 45 passes through a threaded lug 49 on the cylinder or casing 10, and thus feeds the said cylinder or casing up or down by the movement of the handle 46.

ln order to thoroughly pack the pistons 13 and 14, 1 construct them in the manner now to be described.

Each of the pistons consists of a main part 50, sliding over the piston-rod and provided with a shoulder 51 and a reduced threaded portion 52. Fitting overthis reduced threaded portion 52 is an internally-tln'eaded annular member 53, provided with a shoulder 54 and with a reduced portion 55. ln this reduced portion 55 and between the shoulders 51 and 54 is a packing-ring' 56. By this construction a very heavy packing-ring' may be used, such as could not be sprung into position in the o1'- dinary manner.

The operation of my drill is as follows: Supposing the parts to be in the position shown in Fig. 1, the motive fluid will be admitted from the suppl y-opening 33, through the port23, into the lower end of the cylinder through the port 22, and the piston-rod will will be driven downward. At the same time the air will pass out through the port 22 and the exhaust-port 21 in the outside part of the valve to the u-pper exhaust-port 9, whence the air will pass into the open upper end of the cylinder l() and prevent suction in the said upper end of the cylinder. As soon as the piston-rod has traveled down a sufficient distance for the piston to uncover theport 32, leading' into the by-pass 29, air will be admitted through said port and by-pass to the chamber 28 and acting upon the wing 27 will move the inner part 2O of the valve so as to bring' the part of the port 23 passing through the said inner part of the valve into the position shown in dotted lines in Fig. 1. rlhis will cut olf the supplyv of Huid to the lower piston, but will leave the exhaust of the upper end of the piston open, and the piston will continue its travel through the expansion of the motive fluid. As soon as the piston has reached the end of its travel it will uncover the end of the bypass 26 Aand by the action of the iuid on the wing 24 will move the outside part of the valve so as to place the lower exhaust-port 9 in communication with the lower end of the cylinder and also bring the two parts of the port 23 into alinement to supply motive fluid to the upper end of the cylinder. The same operations are repeated on the upward stroke by the piston 13.

Having fully described my invention, what I claim as new, and desire to secure by Letters Patent of the United States, is i 1. In a drill or the like, the combination with a cylinder provided with a piston and having an open end at one side of said piston, of a piston-rod for and of less diameter than said piston projecting through the open end of said cylinder, and means for exhausting motive iiuid from the other side of said piston and discharging it into the side of said cylinder having the open end.

2. 'In a drill or the like, the combination with a cylinder open at both ends and provided with a partition, of a piston rod passing through said partition, a piston carried by said rod at each side of said partition, said piston-rod being of less diameter than said pistons and projecting beyond one of said pistons through one of the open ends of the cylinder, and means for exhausting the motive fluid from the spaces between said pistons and partition and discharging it into the open ends of said cylinder.

3. In a drill or the like, the combination with a cylinder provided with a piston and open at one side of said piston, of a pistonrod for and of less diameter than said piston projecting through the open end of the cyl inder, a port opening into the closed side of said cylinder, a supply-port, an exhaust-port opening' in the open side of said cylinder, and a valve for placing said first-named port alternately in communication with the supply and exhaust ports.

4. In a drill or the like, the combination with a cylinder open at both ends and provided with a partition, of a piston-rod passing' through said partition, a piston carried at each side of said partition, said piston-rod being of less diameter than said pistons and projecting beyond one of said pistons through one of the open ends of the cylinder, a port leading' into the closed end of each side of the cylinder, a supply-port, an exhaust-port leading from the closed end of each side of the cylinder to the open end thereof, and a valve for placing each of said first -named ports alternately in communication with the supply and the corresponding exhaust port.

5. In a drill or the like, the combination with acylinder open at both ends and provided IOO IIO

784, ive

with a partition, of a piston in said cylinder at each side of said partition, a valve com posed of two parts one within the other and arranged adjacent to said partition, exhaust-ports in one of said parts communicating with the exhaustpassages terminating in the open ends oi' the cylinder, a supply-port extending through both of said parts, and means for independently moving the parts of said valve.

6. In a drill or the like, the combination with a cylinder provided with a partition, of a piston in said cylinder at each side of said partition, a rotary valve composed oi' two parts one within the other and arranged adjacent to said partition, exhaust-ports in one of said parts, a su pply-port extending through both of said parts; and means for independently moving each of said parts.

7. In a drill or the like, the combination with a cylinder, of a piston in said cylinder, a valve composed oi' two parts, an exhaustport in one of said parts, a supply-port extending through both ot' said parts, and bypasses controlled by said piston for independently operating the parts oi' said valve.

8. In a drill or the like, the combination with a cylinder, of a piston in said cylinder, a valve composed oi' two parts, an exhaustport in one oi' said parts, a supply-port eX- tending through both ot' said parts, a ley-pass vfor actuating one of said parts, a plurality oi' openings to said by-pass, and a second by-pass tor operating the other of said parts.

9. In a drill or the like, the combination with a cylinder provided with a partition, of a piston in said cylinder at each side of said partition, a single valve composed ot' two independently-movable but cooperative parts arranged adjacent to said partition, a pair of icy-passes controlling the movement of one part of'said Valve, and a second pair of by-` passes controlling the movement of the other part of said valve.

10. In a drill or the like, the combination with a cylinder provided with a partition, of a piston in said cylinder at each side oi said partition, a valve composed of two parts arranged adjacent to said partition, a pair oi bypasses controlling the movement of one of said parts, means for varying the point ot' admission oi' motive fluid to said by-passes, and a second pair of Aby-passes controlling the other of said parts.

11. In a drill or the like, the combination with a cylinder provided with a partition, oi" a piston in said cylinder at each side oi' said partition, a valve composed oi two parts arranged adjacent to said partition, a pai r ot' bypasses controlling the movement of one oi said parts, rotary members in said .by-passes for varying the point of admission of motive Iiuid to said by-passes, and a second pair ol bypasses controlling the movement oi the other of said parts.

12. In a drill or the like, the combination with a cylinder provided with a partition, of a piston in said cylinder at each side of said partition, a rotary valve composed of two parts one within the other and arranged adjacent to said partition, a pair oi' exhaust-ports in the outer part oi' said valve, a supply-port extending through both parts oi said valve, and bypasses for independently operating' the parts of said valve.

In testimony whereoi` I have hereunto set my hand and aiiixed my seal in the presence of the two subscribing witnesses.

CYRUS T. MCCORMICK. L. s]

Witnesses:

H. W. WARD, L. E. ToLEr.. 

